The only physiological movement of the ankle joint is flexion/extension of the foot relative to the leg. However, while walking, there may be lateral movements of the ankle, which can cause ligament damage (sprains) or bone injuries (malleolar fractures). 

ACTION PRINCIPLE: 

Proprioceptive Ankle Brace: Improved proprioception (perception of the body in space) via the use of a compressive knit. Used in the event of mild joint pain or resumption of activities. 

Ligament Ankle Brace: Holds the ankle in an anatomical position using elastic straps. Used in the phase immediately following injury (depending on the severity), or in the resumption of sports phase. 

Ankle Splint: Analgesic and protection action through a more firm immobilisation of the ankle. Its compressive effect can help reduce oedema. Used immediately after an injury or postoperatively.